Apparatus for packing of pulverulent materials



y 1960 c. w. VOGT 2,935,233

APPARATUS FOR PACKING OF FULVERULEZNT MATERIALS Filed June 27, 1956 2 Sheets-Sheet 1 I I 53 f5 ii l g I 12 24 48 :49 l 1/ ,46

2 9 T 22 32 25 34 Z f; 31

INVENTOR 62 Clarence W V095 ERIALS May 3, 1960 c. w. VOGT APPARATUS FOR PACKING OF PULVERULENT MAT Filed June 27, 1956 2 Sheets-Sheet 2 mmwinaaumi I 1104 0 I I I I I I u u a.

APPARATUS FOR PACKING OF PULVERULENI'.

MATERIALS Clarence W; Vogt, Weston, Conn.

Application June 27, 1956, Serial No. 594,152.

27 Claims; (CL. 222-189) This invention relates to the and packaging and more particularly to the method of packaging materials divided: in small size particles and more specifically pulverulent materials as well as to the equipment for forming such packages.

As conducive to an understanding of the invention, it is noted that in packaging for sale in grocery stores, such commodities as fiour, pancake or cake mixes, of small particle size, generally pulverulent, when such commodities are sifted or poured into a receptacle such as a bag or container, the interstitial spaces between the particles and the head room resulting from the settling of the commodity after it is packed, results in an overall package size much larger than would normally be required if such interstitial spaces: and head room were eliminated, with resultant need forgreater shelf space and greater cost of packaging materials.

Furthermore, due to the adverse sheet on certain materials, of the air with its entrained water vapor collected in such interstitial spaces and head room, wide variation may occur in the shelf life of packages of the same commodity thereby limiting the formulation of the materials that can thus be packaged.

Where material of the'above type falls by gravity from a supply hopper, the rate of fall is determined by the impedance due to the air or the frictional resistance between the particles themselvesas well as that caused by the surface of the hopper. In addition, time is consumed while the particles accelerate to their maximum free falling speed. Thus, the filling cycle period is based upon. these factors and where a large number of containers is to be filled, the cumulative filling cycle may take a considerable length of time.

In addition, as the density of the material being packed may fluctuate due to the nature of the material (i.e., where fiour is being packed, different types of wheat may have different densities), and to varying quantities of air and moisture present, there will be variations in the weight of the material in filled containers of a given size from batch to batch and where, in order to fill such uniform size containers with a prescribed minimum weight of material, a separate filling operation is performed, which requires weighing of each filled container, the cumulative time required for such operations for a large number of' containers adds greatly to the cost of packaging.

Where a blower head is used to expel a charge of material from a magazine and the blower head must be moved away from the magazine for filling of the latter, material may collect between adjacent surfaces of the blower head and the magazine so that an imperfect seal may result therebetween when they are juxtaposed.

Thus, upon application ofgas 'underpressure during'the blowing cycle, leakage of such gas as well as of the material may occur.

Furthermore, where such movement of the blower headwith respect to the magazine isetfectedlby lateral sliding, the rubbing action of the adjacent surfaces of 2,935,233 Patented May 3', I960;

ice

the blower head and magazine against the, material'may cause grooving of such surfaces so that the seal therebetween is imperfect with the disadvantages above set forth during the blowing cycle. In addition, where the magazine must be opened for filling it would be difiicult to provide sufiicient suction for rapid filling.

It is accordingly among the objects of the invention to provide a relatively simple method for rapidly filling containers of a given size with assurance that each container will have substantially the same predetermined weight of material in spite of differences in density from batch to batch of the material being packaged and without need for a separate weighing: operation.

Another objectis to provide a relatively simple methed for forming packages containing materials of the above type, in such manner that the finished package will fill rapidly and be devoid of head room and may be of minimum size for a given weight of material, thereby occupying a minimum of shelf space, shipping bulk and wrapping material with resultant lowered cost of packaging, handling and storage.

Still another object is to provide equipment for forming packages of the above type, which is relatively simple in construction, having but few parts which are: not likely to become deranged and which may readily be operated to compact predetermined quantities of material into containers in a minimum period of time" and without leakage of' either gas or the" material being packed.

More particularly, according to one embodiment of the invention, a blower head is provided which may be positioned in sealing engagement with the mouth of the container to be charged, the head being provided with a magazine having an outlet in communication with the container. With the outlet of the magazine closed and with the magazine in communication with a supply hopper, suction is provided to draw material from the hopper into the magazine. Means are provided to cut off the hopper from the magazine and with the outlet of the magazine still closed, to apply gas under pressure against the material in the magazine and when the gas pressure has attained a predetermined value, to open the magazine for discharge of the material therein in compacted form into the container, suitable vents being provided through which the air in the container may be discharged. Means are also provided to regulate the gas pressure applied to the material in the magazine in accordance with the density of such material. The package thus formed in given size containers will be of uniform predetermined weight.

This application is a continuation-in-part of co-pending application Serial No. 585,775, filed May 18, 1956;

In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,

Fig. 1 is a fragmentary side elevational view partly in cross section of the filling equipment,

Fig. 1a is a diagrammatic view of the gas reservoir and controls, j

Fig. 2 is a view taken'along line 2'-2' of Fig. 1',

Fig. 3 is a fragmentary perspective view of the magazine control valve,

Fig. 4 is a side elevational. view of the magazine valve control mechanism, 7

Fig. 5 is a plan view taken along line 5-5 of Fig. 1,

Fig. 6 is a fragmentary view of another embodiment of the magazine, 7

Fig. 7 is a perspective view of packages made with the embodiment of Fig. 6, and.

Fig. 8, is a. sectional. view taken along line 8-8 of Fig. 6.

Referring now to the drawings, thee blower head' shown in Fig. 1 comprises a box-like housing 11, having a substantially frustoconical,. in1et port 12 through its top wall 13 leading into the interior of the housing. Positionedon top wall 13 of the housing 11 and secured thereto as by screws 14- is a hopper 15, also preferably frusto-conical and having its lower end 16. aligned with the mouth 17 of inlet port '12. a

. Rotatably mounted in the housing 11 is a valve memthe housing 11. The surface area of the ring 46 is approximately four times the diameter of the passageway 23,

adjacent inlet port 12, has an annular seat 24 on which .a resilient sealing ring 25 is positioned. A cylindrical retaining member 26 is positioned in housing 11 adjacent the lower edge 27 thereof. The retaining member 26 has a bore 28 therethrough with a curvature substantially corresponding to that of the ball 21 and the lower end of said bore has an inwardly extending annular seat 29 opposed to sealing ring 25. I

Means are provided to urge the retaining member into the housing 11 so that the seat 29 will engage the ball 21 to retain the latter against sealing ring 25 at all times to prevent leakage of material from the inlet port 12 around the outside of the ball 21, and leakage of air or gas back into the hopper 15, when the ball 21 is in closed position relative to the hopper. Under normal operation, ball 21 is not operated when the magazine is under gas pressure.

To this end resilient means are provided reacting against the retaining member 26 to urge it inwardly. In the illustrative embodiment shown, such resilient means comprises a plurality of compressed coil springs 31 each positioned in an associated recess 32 in the retaining member and reacting thereagainst.

Although the coil springs 31 may be retained in the recesses 32 in any suitable manner, as illustratively shown, the magazine 33 of the blower head has a lateral flange 34 at its upper end which is secured to the lower end 27 of the housing as by screws 35, the springs 31 resting against said flange.

Although the ball 21 may be rotated in any suitable manner, in the illustrative embodiment shown, a shaft 37 is provided extending transversely of the housing 11 and rotatably mounted inthe side wall 38 thereof in leak proof relation thereto. The shaft 37, which may be rotated by a handle 39, has its inner end extending through an arcuate notch 41 in the retaining member 26. The inner end of the shaft 37 has flats 42 formed on its pposite sides to render it non-circular in cross section and said flattened inner end is positioned in a slot 43 in a side of the ball 21 to enable the shaft 37 to rotate said ball 21 so that the passageway 22 may be disposed vertically to provide communication between the hopper and magazine 33 or horizontally as shown to close the hopper.- When the passageway 22 is in horizontal position, the passageway 23 will be disposed vertically in communication with themagazine.

As shown in Fig. 1, a clearance space 45 is provided between the ball 21 and the inside of the housing 11. Positioned in the upper portion of the space 45 and encompassing the ball 21 is a ring 46 of sintered or porous metal preferably frusto-conical as shown. The lower edge of the ring 46 rests on an annular seat 47 formed at the upper edge of the retaining member 26. The upper edge of ring 46, which-is of smaller diameter, is pressed by the spring urged retaining member 26 against a resilient O ring 48 positioned in an annular groove 49 adjacent to and encompassing sealing ring 25.

The porous ring 46 forms the inner wall of an annular chamber 51 in communication with a port 52 leading into so that when air under pressure is forced through ring 46 in the manner hereinafter described, there will be a rapid build up of pressure on the material in the magazine for ejection of such material.

Connected to port 52 is a solenoid controlled valve 53 of conventional type. Although the control port 54 of valve 53 may be connected to port 52 in any. suitable manner, as illustratively shown, a flange fitting 55 is screwed on port 54 and retained against the side wall 56 of housing 11 as by screws 57. The valve 53 has an inlet port 58 which may be connected by a line 58' to a gas reservoir R having an inlet 60conne'cted through a pressure regulator valve60' to'a source of gas under pressure and an exhaust port 59 which may be connected to the atmosphere, but preferably is connected to a source of sub-atmospheric pressure.

Communication between ports 58, 54 and 59, 54 is eifected through valves 61, 62'respectively fixed to an armature 62a which is urged downwardly when the solenoid, winding (not shown) of the valve 53 is energized thereby unseating valve 61 and seating valve 62. Valve 61 is normally'spring biased to a closed position and the valve 62 is open when the solenoid controlling the valve 53 is de-energized.

Themagazine 33, as showns in Figs. 1 and 2, is substantially V-shaped having side walls 65 and inclined end walls 66. Positioned in the magazine and preferably formed integral therewith is a partition 67 illustratively an inverted V-shaped member having its apex 68 positioned midway between side wall 65. The member 67, which defines an exhaust chamber 69, has the lower edges of its side walls 70 spaced from the side walls 65 of the magazine, defining slots 71 and suitable vents 72 are provided in end walls 66 of the magazine for escape of air or gas from the exhaust chamber 69.

Aflixed as by screws 75 to the lower end 76 of the 7 magazine and extending over the latter is a plate 77 which has spaced parallel bores 78 therethrough aligned with slots 71. The plate 77 also has vertical passage ways 79 extending through each of said bores 78 and of length substantially equal to the length of slots 71.

Rotatably mounted in each of said bores 78 is a valve member 81 illustratively a rod having a groove 82 along one side thereof of length substantially equal to that of slot 71. Means are provided to rotate said rods 81 so that the grooves 82 therein may be disposed vertically with respect to the associated slot 71 and passageway 79 for flow of material out of the magazine, or disposed horizontally to cut off access from the magazine.

To this end, a lever arm 84 is afiixed at one end to the end 85 of each of the rods 81. The upper ends 86 of the lever arms 84 are pivotally connected to a connecting link 87 as at 88 and said link 87 is pivotally connected as at 89 to a solenoid 91. When the solenoid 91 is de-energized, the rods 81 will be in closed position and when energized the rod 81 will be rotated to dispose the grooves 82 vertically for escape of material from the magazine.

In order to prevent clogging of material as it passes through grooves 82, a vibrator 93 is connected to link 87 to effect vibration of the latter and the rods 81 when they are in open position.

In order to provide an airtight seal between the blower head and the containerto be charged, a sealing strip 95 is atfixed in any suitable manner to the undersurface of plate 77 around the periphery thereof.

The plate 77 has a rectangular opening 97 therethrough aligned with the mouth of exhaust housing 69. The underface of plate 77 at the periphery of the opening is recessed to receive the periphery ofa perforated plate 98 secured in position as by screws 99.

To prevent escape of material through the openings 101 in plate 98, a porous member is positioned across the undersurface of such plate. In the illustrative embodiment shown, the porous member is preferably a strip or Web 102 of porous paper which rides over rollers 103 affixed by brackets 104 to the side walls 66 of the magazine and advanced as by driven rollers 100. The strip of paper 102 may be in the form of a loop or it may be a continuous length wound on a supply reel.

In the operation of the unit above described, a cont-ainer 105, as shown in Figs. 1 and 2 is positioned in a cavity 106 in a mold 107. The container 105 illustratively is of the type having flaps 108 at its mouth which may extend laterally over the upper end of the mold.

The blower head is moved downwardly so that the porous paper sheet 102 is clamped against the flaps which are in turn securely retained against the upper end of the mold, the resilient gasket 95 providing an airtight seal.

With the solenoid 91 de-energized so that the valve members or rods 81 are in closed position, the handle 39 is operated to rotated ball valve 21 so that passageway 22 is disposed vertically. Thus, communication is provided between the hopper 15 and the magazine so that the latter will be charged with the material to be packaged. Although the material in the hopper will fall by gravity into the magazine, in order to speed up the charging cycle, suction may be applied to port 59 of solenoid valve unit 53 which, through open valve 62 and ports 54 and 52, will create a partial vacuum in annular chamber 51. Such vacuum will also be applied through porous ring 46 and passageway 23 into passageway 22 to enhance the rate of fall of the material from the hopper. By reason of the porous ring 46, none of the material to be packaged will pass therethrough.

Inaddition to such vacuum reducing the time for the charging cycle, Where material such as brown sugar is being packaged the vacuum will prevent clogging of such material due to the binding effect of the molasses therein. Furthermore, it tends to eliminate segregation or unmixing of fine and less fine particles or unmixing of smooth particles from rough or flaky particles.

After the magazine has been charged with a predetermined quantity of material, the ball valve may be rotated through an angle of 90 degrees so that the inlet port 12 is sealed and the passageway 23 is disposed vertically in alignment with the magazine. At this time the solenoid valve unit 53 is energized so that valve, 62 closes and valve 61 opens to connect the source of gas under pressure through ports 54, 52 to annular chamber 51. This gas is preferably dried before application to the material so that any gas that should enter the container will have a minimum of water vapor. The compressed gas will pass through porous ring 46 and exert pressure through the ends of passageway 22 against the upper portion of the mass of material in the pass-ageways 22, 23 and in the magazine 33. As the surface area of the porous ring is approximately four times that of the diameter of passageway 23, it is apparent that there will be a rapid build up of pressure on the material in the magazine which is necessary to obtain uniform compactness.

As the gas is diffused by passing through the porous ring 46, channeling of the gas through the powdered material and turbulence above the material are largely eliminated.

When such pressure has built up to say 50 p.s.i., by means of suit-able controls (not shown), the solenoid 91 is energized to rotate rods 82 so that they will be moved to open position. As a result of such relatively high pressure, the material in magazine 33 will be blown at relatively high speed through slots 71, passageways 79-and grooves 82 into the container 105 being charged. As such material enters the container at relatively high speed, the air in the container as Well as that entrained with'the material will be displaced and forced through porous sheet 102. and screen 98 into the exhaust chamber 69 to be, returned. to, the atmosphere through vents 72.

As the valves 82 are normally closed during the intervals between successive blowings, sifting of material into the container with resultant lack of compactness is precluded. In addition, by reason of the. pressure build up, clogging of certain materials such as brown sugar with its high molasses content is, avoided.

When the solenoid 91 is energized to move the rods 82 to open position, the vibrator 93 may simultaneously be energized so that slight vibration will be imparted to the rods 82 to, prevent clogging of material passing through grooves 82.

After the container is charged, the valve unit 53 is again energized to close the valve 61 to shut off the application of air under pressure and valve 62 opened. Although there is a tendency for the. material in the magazine and the passageways 22, 23 to be. forced toward port 52 upon release. of such pressure and, be blown into the atmosphere or the suction system, through port 59, by reason. of the porous ring 46, none of such material, will pass therethrough.

The filling cycle having been completed, the blower head may be raised, from the mold and the charged container removed. As the porous sheet 102 may become slightly clogged due to particles of material adhering to the undersurface thereof during the charging cycle, a new section of porous sheet 102 may be moved into juxtaposition to the screen and thereupon with an empty container positioned in the mold the cycle is repeated.

By adjustment of the pressure regulating valve, the pressure of the gas in reservoir R can be set to a desired amount depending, upon the density of the material being packed, so that uniform weights of materialmay be charged. into the containers of a given size to be filled in spite of variation in density of. such material from batch to batch.

The embodiment shown in Figs. 6 to 8 is similar in many respects to that shown in co-pending application SerialNo. 585,775, filed May 18, 1956.

This embodiment is designed to produce a multi-unit package P including a plurality of units such as P1, P2, P3, P4. Each of the units is generally wedge-shaped, i.e., it is triangular in cross section and is formed by the mold 111 shown in Figs. 6 and 8.v

Each mold element includes a base plate 112 having a plurality of spaced parallel ribs 113, 114, 115, extending outwardly therefrom and diverging end flanges 1 16, 117; Each base plate 112 is also provided with opposite side flanges 118 and 119. Molding cavities are formed between the flange 116 and rib 113, the ribs 113 and IL4, the ribs 114 and 115 and the rib 115 and end flange 11.7 by means of, troughrlike elements of V-shaped cross section formed of porous metal such as sintered bronze powder or the like. The. trough-like elements 120 are retained in position by means of trapezoidal cap pieces 1'21, 122 and 123 screwed or otherwise secured to the upper ends of ribs 113, 114 and 115 and by means of cap pieces, 124 and' 125.

Asshown inFig. 8, the base plate 112 is provided with apertures126and 127 to enable air to escape or be drawn through mold cavity forming elements 120. The apertures 126 and 127 may communicate directly with atmosphere or to a source ofv reduced pressure. I

As illustratively shown in Fig. 8, a thin sheet of thermoplastic material. S, such as, for. example, polyethylene, Mylar, polyvinylindene resin or the like is positioned over the face of the mold 111. This sheet is preferably previously heated in any suitable manner sufficiently to render it plactic and deformable. Suction exerted through the apertures 126 and 127 beneath the porous mold elements 120 and pressure exerted on the upper, surface. of the softened and deformable sheet material S, or both, causes the sheet to be forced down into conformity with the porous elements 120. If desired, the molding cavities may be lined prior to the filling operation.

In operation the edges of 'the sheet S and the portion overlying clampingblocks 121 to 125' are clamped be tweenthese blocks and the porous plate 131 forming the bottom of the magazine 33 of the blower head so that 'plastic deformation of the sheet S will cause the formation of wedge shaped receptacles in the sheet material. The formation of the receptacles is aided by the introduction of the filling material because filling is performed under pneumatic pressure.

The magazine 33' is a cup-shaped member aifixed to the lower end of housing 11' as by screws 35'. The floor 131 of the magazine is of porousmaterialjsuch as sintered bronze and vents 133 to 137 are provided. in the .wall of the magazine 33 shielded by the inverted triangular or inclined guide element 141 to 145 in the bottom of the magazine which form downwardly converging channels for directing the material into the packages. In this way the desired shaping and deformation of the sheet S to form a plurality of wedge shaped cavities or containers takes place, together with introduction of the material. The material also serves to cool the deformed, heated plastic sheet so that it tends to set or harden. Tight joints are formed between the edges of the guide channels and the porous plate 131 by means of solder or the like and a plurality of openings 151 to 154 are provided between the adjacent pairs of inclined guide elements. Secured as by force fit in each of said openings is a hollow insert 155, the inner end of which has a head 156 V which extends laterally so that its beveled undersurface 157 will rest against the associated inclined guide elements.

In the operation of the embodiment shown in Figs. 6 to 8, the magazine 33' is filled in the same manner as the magazine 33 shown in Figs 1 and 2, for example. It will be understood that the sheet S is of greatly en larged thickness beyond what it would be in normal useage and alsovis shown as not having been previously 'formed to conform to the inside surfaces of cavities 11 and 12. However, such preforming prior to commencement of the fillingoperation may be preferred in some instances.

When gas under pressure is applied tothe material in the magazine, also in the manner previously described,

ing is thus made possible by the escape of compressed interstitial gas through'the pores of the material of the inserts and thence to their adjacent porous plates 131 and thence out of vents 133 to 137. However, with material having relatively high viscosity these inserts may be of non-porous material as shown, since with such material there is no likelihood of sitting of the material through the properly shaped and sized filling orifices, prior to the proper pressure build up of gas used to accomplish the filling operation as hereinbefore described. In addition,

the use of the insert permits different size passageways ball valve 21. 'Due to this arrangement when means 'terial to form the container.

handle 39 and valve 53, a simplified rapid and fully automated cycle may be performed.

The combined blowing and exhaust operations of a complete cycle actually only requires a fraction of a second and the remaining portions of the cycle, i.e., rota: tion of the valve 21 to fill position, charging of the maga zine and rotation of the valve 21 back to blow position, may be accomplished with corresponding rapidity and while the blower head and magazine attached thereto are unclamped from the conveyor system carrying the containers to be charged, the conveyer is indexed to align a new container or group of containers with the magazine, and the blower head and magazine clamped with respect to such container or containers.

With the method and equipment above described, an intermittent high speed operation can be accomplished, producing uniform size packages with substantially equal weights of material regardless ofvariations of density of the material from batch tobatch.

Furthermore, by reason of the compacting of the non form-retaining material, a given weight of material will occupy a considerably smaller volume than a corresponding non-compacted Weight of the same material. Thus, for certain pulverulent materials compacted at a pressure of p.s.i., for example, the volume of the package may be approximately sixty percent of the volume of an equivalent weight of non-compacted material. Consequently, the amount of shelf space to store and display the package is greatly reduced as is the quantity of ma.-

In addition, as interstitial spaces are reduced to a minimum and as there is substantially no head room, there will be little air with its entrained water vapor in the completed package which gives increased flexibility in the type and formulation of materials that can be packaged. 7

As many changes could be made in the above method and equipment, and many apparently widely different emnew and desire to secure by Letters Patent of the United States is:

1. Apparatus for filling containers comprising a magazine having an inlet for supplying material to said magazine and a floor having a discharge passagewaytherein for said material, means for opening and closing said inlet, means to supply gas under pressure to said magazine to force material therein through said discharge passageway, and a valve in said discharge passageway for opening and closing it to control flow of material therethrough.

2. The combination set forth in claim 1 in which normally closed valve means controls said discharge passage Way and means are provided to open said valve means when the gas pressure has attained a predetermined value.

3. The combination set forth in claim 1 in which said magazine has a vent and a partition is provided in said magazine between said vent and said discharge passageway, said partition defining an exhaust chamber, said magazine floor having an opening defining the mouth of said exhaust chamber and a screen is positioned over said niouthi 4. The combination set forth in claim 3 in which said screen is a web and means are provided to effect movement said web with respect to said opening.

5. Equipment of the character described comprising a housing having an interior space and an inlet and an outlet communicating'with said space, a valve in said housing between said inlet and outlet for controlling passage of material from said inlet to said outlet,- a magazine aligned with said housing and in communica- Q tion with said outlet, said magazine having a floor with adischarge passageway therethrough, and means to supply gas under pressure to said interior space to force material in said magazine through said discharge passageway.

6. The combination set forth in claim in which a supply hopper is mounted on said housing in communi cation with said inlet and means are provided to apply suction to said interior space to draw material therethrough from said hopper into said magazine.

7. The combination set forth in claim 5 in which a supply hopper is mounted on said housing in communication with said inlet, means to apply suction to said interior space to draw material from said hopper into said magazine while restraining application of gas under pressure to the contents of said magazine, a normally closed valve means controlling said discharge passageway and means to open said valve means aftersaid suction has been cut oh and the pressure of the gas has attained a predetermined value.

8. The combination set forth in claim 5 comprising a supply hopper having an outlet mounted on said housing in juxtaposition to said housing inlet, and said valve having a diametrical passage and a radial passage intersecting the diametrical passage, means for maintaining said valve in pressure tight relation to said housing around said housing inlet, said diametrical passage being in alignment with said housing inlet to establish communication with said hopper outlet when said diametrical valve passage is vertically disposed.

9. Equipment of the character described comprising a housing having an interior space and an inlet and an outlet communicating with said interior space, a valve member rotatably mounted in said interior space between said inlet and outlet for controlling flow of material from said inlet to said outlet, said valve member having a passageway extending diametrically therethrough and a radial passageway leading into said diametrically extending passageway, means to rotate said valve member between a position to align said diametrically extending passageway with said inlet and outlet and a position to seal said inlet and align said radial passageway with said outlet, a porous member having relatively minute passageways located in said housing and encompassing a portion of said valve member adjacent said inlet and defining a chamber at the outer portion of said interior space and separating said chamber from the central portion of said interior space, said housing having a port leading into said chamber.

10. Equipment of the character described comprising a housing having an inlet and an outlet, a ball member rotatably mounted in said housing between said inlet and outlet, said ball member having a passageway extending diametrically therethrough and a radial passageway leading into said diametrically extending passageway, means to rotate said ball member between a position to align said diametrically extending passageway with said inlet and outlet to permit flow of material from said inlet to said outlet and a position to seal said inlet and align said radial passageway with said outlet, a porous filter member having relatively minute passageways therethrough, located in said housing and encompassing a portion of said valve member adjacent said inlet and defining a chamber at the outer portion of said interior space and separating said chamber from the central portion of said interior space, and means communicating with said space for supplying gas to said housing to force material in said housing through said outlet.

11. The combination set forth in claim in which a surface of said porous member forms a wall of said annular chamber and said surface has an area several times the cross sectional area of the radial passageway in said ball member.

12. The combination set forth in claim 10 in which the cross sectional area of the radial passageway is substantially equal to that of said diametrically extending passageway, a surface of said porous member forms a-wall of said annular chamber and said surface has an area. substantially four times the cross sectional area of the radial passageway.

13. The combination set forth in claim 10 in which a resilient seal ring is positioned adjacent said inlet coaxial therewith and means are provided to retain said ball member against said seal ring, the latter defining a seat for said ball member.

14. The combination set forth in claim 10, in which a resilient seal ring is positioned adjacent said inlet coaxial therewith, a cylindrical retaining member is positioned in said housing on the side of the ball opposed, to said seal ring, said retaining member having a bore with an annular seat at its lower end, and resilient means reacting against said retaining member to urge said annular seat against said ball member and said ball member against said seal ring, said seal ring also defining a seat for said ball member. i

15. The, combination set forth in claim 10 in which a resilient seal ring is positioned adjacent said inlet coaxial therewith, a cylindrical retaining member is positioned in said housing on the side of the ball member opposed to said seal ring, said retaining member having a bore with an annular seat at its lower end, said porous member is seated at its lower edge on the upperedge of said retaining member, and resilient means reacting against said retaining member to urge said annular seat against said ball member, said ball member against said seal ring and the upper edge of said porous member against the portion of the inner surface of the top wall of the housing encompassing said seal ring.

16. The combination set forth in claim 15 in which the portion of the inner surface of the top wall of the housing encompassing said seal ring has an annular groove, a resilient ring is positioned in said groove and the upper edge of the porous member is urged against said resilient ring.

17. The combination set forth in claim 10 in which said ball member has a slot in the side thereof and the means to rotate said ball member comprises a shaft er;- tending through the side wall of the housing into said slot, said shaft having flats on its inner end to render it non-circular in cross section to coact with the side walls of said slot for rotation of said ball member.

18. The combination set forth in claim 10 in which a valve unit is provided having a control port connected to the port of said housing leading into said chamber, said valve unit having a pressure port and an exhaust port and means in said valve unit alternatively to connect said pressure port and said exhaust port to said control port.

19. The combination set forth in claim 18 in which said last named means comprises a pair of valve members, one of said valve members normally being in closed position to cut off communication between said pressure port and said control port and the other of said valve members normally being in open position to provide communication between said exhaust port and said control port.

20. The combination set forth in claim 10 in which a magazine is affixed to the bottom of said housing in communication with said outlet, said magazine having a discharge passageway through its floor and a vent and a partition in said magazine between said discharge passageway and said vent, said partition defining an exhaust chamber.

21. The combination set forth in claim 10 in which a magazine is afiixed to the bottom of said housing in communication with said outlet, said magazine having a discharge passageway through its floor and a vent and a partition in said magazine between said discharge passageway and said vent, said partition defining an exhaust chamber, normally closed valve means in said discharge passageway and means to actuate said valve means to mamas .open the latter for discharge of material from said magazine.

22. The combination set forth in claim 21 in which said exhaust chamber has a mouth extending parallel to a discharge passageway through its floor and valve means control said discharge passageway.

24. The combinationset forth in claim 23 in which means are provided to vibrate said valve means when it is in open position with respect to said passageway.

25. The combination set forth in claim 10 in which a magazine is aflixed to the bottom of said housing in communication with said outlet, said magazine having a floor with a discharge passageway therethrough, a partition in said magazine defining an exhaust chamber, said magazine floor having an opening defining the mouth of said exhaust chamber, said opening being spaced from said discharge passageway and a porous member positioned over the mouth of said exhaust chamber.

12 26. The combination set forth in claim 25 in which a rigid perforated plate is positioned over said opening and said porous member is a web extending across said plate, means being provided to efiectmovement of said web with respect to said opening.

- 27. The combination set forth in claim 10 in which source of gas under pressure is provided, means to regulate said pressure and means to connect said source to said control port.

References Cited in the file of this patent UNITED STATES PATENTS 368,545 Muller Aug. 16, 1887 1,149,844 Lieber Aug. 10, 1915 1,784,795 1 Skonberg Dec. 9, 1930 1,882,668 McCabe Oct. 18, 1932 2,319,192 Sheldon May 11, 1943 2,381,454 Huth Aug. 7, 1945 2,708,542 Gray et al May 17, 1955 2,780,247 Claassen Feb. 5, 1957 

